Question: God tells Abraham and Isaac that their descendants (Hebrews) will be as numerous as the stars. Considering the number of stars there are in the universe, that would have to be on the order of 1020 Jewish people. Is this not a failed prophecy?
Response: In Genesis:15:5 we read, “And he brought him forth abroad, and said, Look now toward heaven, and tell [count] the stars, if thou be able to number them: and he said unto him, So shall thy seed be.”
To Abraham, a man whose wife was barren, the Lord issued a challenge to him to count the stars with his unaided eye (if he were able) and promised that in a like manner, “so shall thy seed be.” With no telescope, Abraham could hardly arrive at a total of 1020 stars.
Indeed, there is no indication that Abraham even began counting stars before it was said, “And he believed in the LORD; and he counted it to him for righteousness” (Gn 15:6). The simple point is that Abraham looked at the sheer number of stars that the unaided eye could see and he believed God.
The Lord also speaks of the “sand along the seashore” and this hyperbole is clearly indicating a number of descendants far more than he could imagine.